New Solar Cells 25% more efficient

[General Havoc]

http://www.chicagotribune.com/business/sns-rt-us-solar-celltre8171ib-20120208,0,3653884.story

A new type of solar cell which could boost the efficiency of solar panels by over 25 percent compared to silicon-based cells has been developed by British scientists, but they need another two or three years to assess whether it is commercially viable.

Scientists at the University of Cambridge have developed a hybrid solar cell which is capable of converting 44 percent of sunlight into electrical power, 29 percent more than traditional cells' capability of 34 percent, they said in the journal NanoLetters on Wednesday.

Solar cells convert the sun's energy into electricity. They absorb energy through semi-conductor materials like silicon from light particles called photons, generating electrons to make electricity.

However, silicon solar cells cannot extract all the energy in a photon and much of the energy from the more energetic blue photons is lost. Usually a solar cell generates one electron from each photon captured.

"We present the first hybrid solar cell that utilizes a phenomenon called singlet exciton fission to generate two electrons for each absorbed photon in the organic material," Bruno Ehrler, lead author of the research, told Reuters.

Hybrid cells are not new and were first developed in 1996 but their efficiency needs to be increased and stabilized before they can be commercialized.

"These (hybrid cells) are the first of their kind so it is very difficult to estimate when they will go into commercialization," Ehrler said.

"The firm Eight19 works closely with the group and will put our cells in production if they turn out to be commercially viable. However, in order to assess that we need to investigate the devices further. This might take 2 to 3 years," he added.

The price of silicon-based panels and cells has fallen dramatically over the past year, cutting profit for manufacturers and putting them under more pressure to produce even cheaper products.

Fledgling technology such as concentrating photovoltaic solar, which multiplies the sun's powers up to hundreds of times, has gained the backing of some large industry players due to its promise of delivering cheaper electricity than traditional solar panels.

The university research team's new hybrid cells could help to reduce costs as well, Ehrler said.

"Since our materials can be dissolved and processed by roll-to-roll printing, we expect the actual cost of a solar panel be much lower than (with) conventional silicon solar cells."

"On an industrial scale, the cost of making the basic silicon solar cell would dominate over the cost of an organic layer printed on top of it. However, this discovery is in an early stage so it is difficult to predict the final cost and device structure," he added.

Any developments that might push solar into a more viable energy source is good news.

[Josh]

My layman's understanding of the field isn't that solar efficiency itself is the big hangup, it's power storage and transmission that's the issue. It's conceivable to enhance power production for southwestern cities via solar, so long as the solar doesn't assume too much of a percentage of base load due to the inability to insure power production on those cloudy days. Then as you move away from the 'sunny over three hundred days a year' areas and into more rainy/cloudy environments, you're pretty much out of luck. Running grids in the desert to power far-away areas runs into power transmission issues.

All that said, as a resident in one of the aforementioned mostly sunny desert regions I'll be happy to get better solar power capacity over a smaller area so long as we can shield the panels from the golf-ball sized hail we get when it does storm up. That, they do seem to have gotten down. Over the past five years, there's been a noticeable transition locally from the previous wind-power setup to a solar setup for irrigation in the cotton farms.

[Cynical Cat]

Cool. It doesn't do me any good directly, but people with plenty of hydroelectric shouldn't complain.